Mustafa Shaikh — essays and notesHow distributed systems fail, and the design decisions that stop them.https://shaikhmustafa.dev/en-usExactly-once is a promise you make to a personhttps://shaikhmustafa.dev/essays/exactly-once/https://shaikhmustafa.dev/essays/exactly-once/Networks deliver at most once or at least once. "Exactly once" is something you build at the edges, one side effect at a time.Tue, 03 Nov 2026 00:00:00 GMTDead or just slow?https://shaikhmustafa.dev/essays/failure-detection/https://shaikhmustafa.dev/essays/failure-detection/Every failure detector trades how quickly it notices a death against how often it mourns a node that was only late. You get to pick the trade, not escape it.Tue, 03 Nov 2026 00:00:00 GMTA queue is a promise to be slow laterhttps://shaikhmustafa.dev/essays/queues/https://shaikhmustafa.dev/essays/queues/Utilization near 100 % looks like efficiency on a dashboard and feels like an outage to the people waiting. Queues don't remove overload; they postpone it.Tue, 03 Nov 2026 00:00:00 GMTRetries are a load amplifierhttps://shaikhmustafa.dev/essays/retries/https://shaikhmustafa.dev/essays/retries/A retry policy is a promise about how much extra traffic you will send at the worst possible moment. Most teams never read the promise.Tue, 03 Nov 2026 00:00:00 GMTMask personal data before it has a chance to be loggedhttps://shaikhmustafa.dev/essays/pii-masking/https://shaikhmustafa.dev/essays/pii-masking/If raw personal data reaches your logs, your analytics or your search index even once, you have a cleanup project, not a feature. Masking belongs at the front of the pipeline.Tue, 03 Nov 2026 00:00:00 GMTCoding agents need a map, not a bigger prompthttps://shaikhmustafa.dev/essays/agents-need-a-map/https://shaikhmustafa.dev/essays/agents-need-a-map/AI coding agents fail on real codebases for the same reason new hires do — they can't see the shape of the system. Give them a map, a narrow brief and a way to prove their work.Tue, 03 Nov 2026 00:00:00 GMTTranslations are a build artifact, not a spreadsheethttps://shaikhmustafa.dev/essays/translations/https://shaikhmustafa.dev/essays/translations/Most internationalisation bugs come from treating translated text as content someone pastes in. Treat it like code — keyed, versioned, tested and shipped — and most of them disappear.Tue, 03 Nov 2026 00:00:00 GMTMigrating off a monolith without stopping the moneyhttps://shaikhmustafa.dev/essays/strangler/https://shaikhmustafa.dev/essays/strangler/The strangler pattern is easy to draw and hard to finish. Most of the difficulty is in the data, and most of the risk is in the last step nobody schedules.Tue, 03 Nov 2026 00:00:00 GMT